ES2739881T3 - Packing machine - Google Patents

Abstract

Packing machine for packing groups of products (100) with an extensible plastic film (50) in order to form packages (200), comprising: - first conveyor means (2) to support and move a group of products (100 ) along a direction (A) of movement inside the packaging machine (1); - support means (3; 103) for receiving said first conveyor means (2) and for supporting said group of products (100) and including first holding means (4; 104) arranged to support an initial flap (51a ) of said film part (51) when packing said group of products (100); - a packaging unit (10) for wrapping with a part (51) of film (50) having a predetermined length said group of products (100), supported by said support means (3; 103), in order to form one package (200); - a supply unit (30) of said film (50) for feeding said packaging unit (10) with said film part (51) having a predetermined length, separated from said film (50) unwound from a reel (55) ) respective; - containment means (6; 60) arranged to rest on at least side walls of said group of products (100) in order to support and guide said products (100) when the latter move along said direction (A) for moving through said packaging unit (10) and / or supporting and containing said group of products (100) during packaging with said part (51) of film (50); characterized in that said first fastening means includes at least one support element (104) of said support means (103), said support element (104) comprising a support wall (141) that forms a plane ( M) of support for said group of products (100) and air suction means (40), specifically, which come out in a base wall (148) of said support element (104) opposite said wall (141). ) of support, and arranged to absorb and support by depression said initial flap (51a) of said part (51) of film during packaging, wherein said element (104) of support of said support means (103) comprises a pair of first tapes (142), which are flexible, endless and arranged to rest on them along respective sections (T) of operation of said part (51) of film during packaging, said first tapes ( 142) in order to move in the operating sections (T) or respective along said travel direction (A) together with said package (200) exiting said packaging unit (10) to allow said support element (104) to separate from said package (200).

Description

DESCRIPTION

Packing machine

The invention relates to packaging machines for packaging products with a plastic film, specifically, it refers to a packaging machine arranged to package groups of products in packages by means of an extensible plastic film.

Packing machines are known, the so-called shrink wrapping machines, which allow packaging groups of products with different shapes and sizes, such as bottles, cans, jars, cans, etc., with a film made of plastic material that contracts with heat, which is a material capable of contracting when heated, for the purpose of packing, compacting and blocking the products and, therefore, forming a package or wrap.

Normally, shrink wrapping machines include a conveyor system that moves products to be packed successively through a series of operating stations. Downstream with respect to a composition station, where the products are divided and separated into groups with a desired composition (for example, according to two or more adjacent rows with two or more products each), a packing station is arranged in where the product groups are packed successively and individually with a part of plastic film having a suitable length, cut from a film reel, in order to form respective packages or packages. Specifically, the products are wrapped with the film in order to form a ring or tube, with two opposite transverse fins of the film part overlapping and fixed to each other, usually at the base of the products. Because the film is rolled without exerting any tensile force, it is not necessary to contain and support the products (which are especially unstable if bottles are included) on their sides.

In a subsequent heating station (tunnel or shrink oven), the rolled film part forming a ring shape around the products contracts due to the effect of heat in order to wrap and tightly compact the products and form the package or final container, which leaves the product group open on the sides. When contracted, the film exerts a packing force that does not destabilize the products.

Because the film part is arranged around the product group precisely, the heat-shrinkable plastic film can be printed with writings, drawings, decorations or the like, which are arranged in the package at the desired positions, such as the market currently requires, specifically, in the beverage sector (bottles, cans).

A drawback of known shrink wrapping machines that use heat shrinkable plastic film is the high operating costs due to the cost of the plastic film (normally, polyethylene, PTFE, PVDF, high density PVC and with a suitable thickness between 100 and 200 | jm) and the energy consumption of the shrink oven, where the air that strikes the film must be heated to a temperature between 170 ° and 200 ° C.

Another drawback of known shrink wrapping machines is that they do not allow packaging products that cannot be subjected to heating at the temperatures reached in shrink ovens.

In order to overcome these drawbacks and improve the economics of product packaging, various solutions have been developed that allow the use of a cold-stretch plastic film, that is, without using shrink ovens. In fact, the extensible film is a low density plastic film that can be used with a thickness between 10 and 25 jm and a percentage between 250 and 400% of the original length can be stretched, thus being more convenient and economical than a film that can contract with heat.

DE 3910823 describes an apparatus for packaging a group of bottles or containers in the form of bottles with an extensible film, comprising a conveyor that moves the bottles to a packing station. The packing station is provided with fixed guide rods that rest on the necks and cavities made in the lower part of the bottles, thus supporting the bottles vertically and laterally, and packing means comprising a structure of ring that rotates around a horizontal axis and that supports a film reel. During the rotation of the ring, the film wraps around the group of bottles and the guide stems. Next, the group of packaged bottles is pushed out of the packing station, with the guide stems separating from the film, by a group of subsequent bottles to be packaged moving through the conveyor.

A drawback of the packaging apparatus described above is that it does not allow packaging types of containers that are different from bottles with a neck and, in fact, require replacement of the guide stems based on the shape and dimension of the bottles.

EP 1288127, of the same applicant, describes an apparatus for packaging groups of products with a cold extensible film, comprising a plane along which the products move to form groups and a first packing station provided with means for unwinding a Extensible film and previously forming a first part of the film that envelops with a tubular shape first pre-forming means comprising a plurality of parallel stems with respect to a direction of movement of the products. The stems of the first preforming means are movable between a fully closed position, where the film wraps the stems in order to form the first tubular part, an open position, where the stems extend and stretch the film transversely, extending the first tubular part in order to allow the insertion of the group of products, and a final position in order to allow the group of products packed with the film to exit. The packaging means includes a ring structure that rotates around a horizontal axis and supports a coil from which the film is unwound. A second packing station, substantially identical to the first packing station, is arranged downstream with respect thereto for the purpose of packing the product group with a second part of tubular film. Between the two packing stations there is a rotating table that supports and rotates the group of products that leaves the first packing station 90 °. WO 2011/024050 describes an apparatus for packaging in groups of containers for liquids comprising a plurality of packing stations, each of which provided with a clamping unit formed by two U-shaped clamps, which are movable at along a longitudinal direction in order to hold and block a group of products vertically leaving their lower and upper parts free. The packaging station includes film packaging means, which comprise a ring structure, which rotates around a parallel horizontal axis with respect to the longitudinal direction and which supports a reel from which the film wrapping the products is unwound during the rotation of the ring structure. A cutting element, movable in parallel with respect to the longitudinal direction, is used to cut the film and separate the part of film that wraps the products with respect to the part from the coil.

A drawback of the known packaging apparatus described above is that they do not allow the use of printed films in the packaging of product groups in packages. Specifically, the packaging means of the aforementioned apparatuses, which include rotating rings that support film reels, do not allow the unwrapped and separated film portions of the film reel to be accurately and reproducibly wrapped and that wrap the products.

Another drawback of the aforementioned packaging apparatus is the reduced operating autonomy due to the small dimensions of the film reel, which is supported and rotates around the products by means of the rotating ring. Therefore, frequent machine shutdowns and corresponding production interruptions are necessary for more or less prolonged periods to replace spent film reels.

EP 1431185 A1 also describes an apparatus for packing according to the preamble of claim 1.

An objective of the present invention is to improve known packaging machines arranged to pack groups of products in packages, specifically, packaging machines that use a film made of extensible plastic material to package groups of products in packages. Another objective is to obtain a packaging machine that allows packaging groups of products in packages using a printed film, specifically, which allows a portion of film having a predetermined length to be arranged in a precise and reproducible manner around the products.

Another objective is to raise awareness of a flexible and versatile packaging machine that allows packages of products that have different sizes and dimensions to be packaged in a precise and efficient manner, without the need for complicated adjustment and / or regulation operations. and difficult. Another additional objective is to make known a packaging machine that has a great autonomy of operation, specifically, which allows to replace the spent film reels without having to stop production.

These and other objectives are achieved by a packaging machine according to one or more of the following claims.

It would be possible to improve the understanding and implementation of the invention by referring to the accompanying drawings, which show some illustrative and non-limiting embodiments, and in which:

- Figure 1 is a schematic top plan view of the packaging machine of the invention associated with groups of products to be packaged and packed in packages;

- Figure 2 is a partial front view of the packaging machine of Figure 1 in an operating stage;

- Figure 3 is a schematic side view of the machine of Figure 1 where some parts have been removed in order to more clearly show a packaging unit and a supply unit of a packaging film;

- Figure 4 is an enlarged and partial view of the packaging unit and the film supply unit of Figure 3 in an operating stage;

- Figures 5 and 6 are partial front views of the packaging machine of Figure 1 in two additional respective operating stages;

- Figure 7 is an enlarged and partial plan view of Figure 1 showing guide means in a release position;

- Figure 8 is a schematic and partial side view of the packaging unit;

- Figure 9 is a front sectional view of the packaging unit of Figure 7;

- figure 10 is a side view of support means of the machine of figure 1 in an open position;

- Figure 11 is an enlarged and partial side view of the support means in a closed position to support an initial film flap;

- Figure 12 is a top plan view of the support means in the closed position;

- Figures 13 and 14 are views like that of Figure 8 showing the packaging unit in two respective different working positions with different respective products to be packaged;

- Figures 15 to 21 are schematic and partial side views of the packing unit in respective packing stages of a group of products;

- Figures 22 to 24 are schematic and partial side views of the packaging unit in a film setting stage;

- Figure 25 is a partial side view of a variant of the packaging machine of the invention showing an insertion arm of the packaging unit;

- Figure 26 is a partial plan view of another variant of the packaging machine of the invention showing the support means of the product groups;

- Figure 27 is a schematic and partial side view of the packaging unit of the packaging machine of Figure 26 showing the insertion arm and the support means in an operating stage;

- Figure 28 is a schematic side view of another variant of the packaging machine of the invention showing packaging means of the products;

- Figure 29 is a schematic side view of the variant of the packaging machine of Figure 28 showing actuation means of the packaging means;

- Figure 30 is a schematic side view of another variant of the packaging machine of the invention showing packaging means of the products;

- Figure 31 is a partial side view of another additional variant of the packaging machine of the invention showing unwinding means and cutting means of the supply unit;

- Figures 32 and 33 are, respectively, a side view and a perspective view of support means and containment means of the products of another variant of the packaging machine of the invention;

- Figure 34 is a top plan view of the support means and the containment means of the variant of Figures 32 and 33;

- Figure 35 is a schematic top plan view of another variant of the packaging machine of the invention.

Referring to Figures 1 to 14, a packing machine 1 is shown arranged to pack groups of products 100 with a film 50 of extensible plastic material for the purpose of forming packages The packaging machine 1 includes first conveyor means 2 to support and move a group of products 100 that enters along a direction of travel A, support means 3 to receive from the first conveyor means 2 and support the group of products 100 during packaging with a film, a packaging unit 10 for wrapping the product group 100 and the support means 3 with a film part 51 having a predetermined length for the purpose of forming a package 200, and a unit 30 of supplying the film 50 to supply to the packing unit 10 the part 51 of the film having a predetermined length, separated from the film 50 and unwound from a respective reel 55. The length of the film part 51 is calculated according to the shape and / or dimensions of the product group 100 to be packed and the desired number of film turns to be applied to the products.

The support means 3 comprise first fastening means 4 suitable for supporting an initial flap 51a of the film part 51 during the packing of the product group 100, while the packing unit 10 includes an insertion arm 11, which is movable and arranged to hold the initial flap 51a leaving the supply unit 30 and transfer it to the support means 3, for the purpose of being held and locked by the first fastening means 4, at an initial stage of packing adjustment. In addition, the packaging unit 10 includes packaging means 12 for unwinding the film part 51 from the supply unit 30 and wrapping the product group 100 therewith.

In the embodiment shown in the figures, the first conveyor means 2 receives the products 100, for example, containers for liquids, such as bottles, small bottles, cans, cans or the like, from supply conveyor means 8 arranged transversely, of specific form, orthogonally, with respect to supply direction A.

The first conveyor means 2 comprise a sliding plane 25 which is coplanar with a support plane M formed by the support means 3, and mobile pusher means 26 and arranged to rest on the product groups 100 and push them apart from each other. along the direction of travel A. More precisely, the pusher means, of known type and not shown in detail in the figures, comprise a plurality of pusher cross members 26 whose ends are mounted on respective endless moving chains, movable along an operating section, in order to rely on respective product groups 100 and, therefore, to push them, along the direction of travel A, of the supply conveyor means 8 to the packing unit 10. Second conveyor means 7 are arranged downstream with respect to the packing unit 10 in order to support and move the packages 200 along the direction of travel A, when leaving the packing machine 1. The second conveyor means 7 comprise, for example, a belt or motorized conveyor of known type and not shown in detail in the figures.

As shown specifically in Figures 10 to 12, in one embodiment of the packaging machine of the invention, the first fastening means includes two support elements 4 of the support means 3, said support elements 4 being adjacent and opposite, defining a support plane M for the group of products 100, and moving transversely with respect to the direction A of travel between a closing position B1 and an opening position B2. In the closed position B1, the support elements 4 are supported with each other in order to block an initial flap 51a of the film part 51 during packaging; in the opening position B2, the support elements 4 are mutually separated to allow insertion or release of the initial flap 51a of the film part 51, as explained in more detail below in the description. Each support element 4 includes a support part 47 which has an elongated shape (for example, a list made of elastic material) and arranged in parallel with respect to the direction A of travel. In the closed position B1 of the support means 3, the support parts 47 of the two support elements 4 are arranged against each other in order to support and block the initial flap 51a of the part 51 of inserted and arranged film between them (figure 10).

Each support element 4 further includes a substantially horizontal support wall 41, suitable for supporting the product group 100 and forming the support plane M. Each support element 4 further includes a first flexible, endless, mobile belt 42 arranged so that the film portion 51 rests thereon along a working section T during packing. The first belt 42 is driven to move, in the operating section T, along the direction of travel A together with the package 200 leaving the packing unit 10 in order to allow the support elements 4 to separate of the package 200. The first belt 42 wraps a plurality of pulleys 43, 44, 45 that are rotatable about respective orthogonal axes with respect to the support wall 41, that is, with respect to the support plane M. The first tape 42 has an almost orthogonal support surface with respect to the support wall 41, which can be contacted in the operating section T with the film part 51 that surrounds the product group 100. In the operating section T, the first tape 42 leaves the respective support element 4 so that the film part 51 rests on it.

Inside the respective support element 4, the first belt 42 wraps a first pulley 43, rotatably driven by a respective first motor 46, a pair of second return pulleys 44 and a third return pulley 45, the return pulleys 44, 45 rotating and free.

In a variant of the packaging machine 1, which is not part of the scope of the invention, not shown, the support elements 4 of the support means 3 (which also function as the first fastening means of the initial fin 51a of the part 51) do not include mobile tapes that rest on the flexible material and that can be folded. In this case, the separation of the packed products 100 from the support means 3 takes place thanks to the size and shape of the support elements 4, which facilitate the sliding of the material, that is, from the film part 51.

The packaging machine 1 of the invention also comprises guiding means 5 for supporting the side walls of the package 200 and guiding the latter when leaving the packing unit 10 and separating from the support means 3.

The guide means 5 are movable along the direction of travel A between a holding position D1, where they are supported on the package 200 inside the packing unit 10, and a release position D2, wherein said guide means 5 are separated from the packing unit 10 and arrange the package 200 in the second conveyor means 7.

The guide means 5 comprise one or more pairs of supporting rods 61, for example, four pairs, the supporting rods 61 of each pair being parallel to each other and with respect to the direction A of travel and opposite, separated from each other by a distance equal to the width or transverse dimension of the package 200 in order to rest on its side walls.

The pair of support rods 61 are vertically separated from each other for the purpose of relying on products 100 having different dimensions and sizes and supporting them vertically. The support rods 61 are supported by a pair of columns 68 that are substantially vertical and fixed to a mobile support carriage 69 linearly along the direction of travel A, in both directions, between the holding position D1 and the position D2 release. The support rods 61 are fixed in an adjustable manner along the columns 69, according to the shape and dimensions of the products 100.

The support rods 61 are provided with respective second movable belts 62 which are endless, arranged to rest on opposite side walls of the package 200 and rotate so as to move said package 200 along the direction of travel A when leaving the packing unit 10. More precisely, and as explained in more detail below in the description, the guide means 5 cooperate in the transfer of the package 200 of the packing unit 10 to the second conveyor means 7. Referring specifically to Figure 6, the second belt 62 of each support rod 61, which has, for example, a flat shape, wraps a pair of respective pulleys 63 that rotate around respective axes that are orthogonal with respect to the M support plane. At least one of the pulleys rotates by means of a second motor 64 fixed to the support carriage 69. The second tape 62 has a respective support surface that is substantially orthogonal with respect to the support plane M and that contacts a side wall of the package 200. In the embodiment shown, the second ribbons 62 of the support rods 61 that are supported on the same side wall of the package 200 (ie, the support rods 61 aligned and superimposed vertically on the same side of the package 200, fixed to the same column 68) are driven by the same second motor 64, for example, a motor electric swivel

The containment means 6 are arranged to rest on the product group 100 and guide it laterally from the first conveyor means 2, along the direction of travel A, and, specifically, inside the unit 10 of packaging.

The containment means 6 comprise a pair of side panels 65, fixed to the frame means of the packing machine 1, which have an elongated shape and arranged in parallel and opposite in order to rest on the product group 100 in its opposite sides.

In the embodiment shown, each side panel 65 has a through opening 66 to allow the pusher cross members 26 to pass through and move and a pair of guide projections 67, 67 'having a flat and elongated shape, arranged to support laterally during packing the products 100 to be packed with part 51 of film. The flat and elongated shape of the side panels 65 allows the latter to be easily separated from the package 200 at the end of the packaging when said package is pushed out of the packaging unit 10 by a group of products 100 to be packed in cooperation with the guide means 5 (thanks to the second ribbons 62).

Referring specifically to Figure 3, the packaging unit 10 comprises an insertion arm 11, movable and arranged to hold the initial flap 51a when leaving the supply unit 30 and to transfer it to the support means 3 for that purpose. if secured and locked by the latter, in an initial adjustment stage of the packing machine before packing. The packaging unit 10 also comprises packaging means 12 for unwinding and moving the film part 51 from the supply unit 30 and wrapping the product group 100 and the support means 3 therewith.

The packing means 12 of the packing unit 10 comprise a support ring 13 which rotates around a packing X axis, in parallel with respect to the direction of travel, a plurality of packing rollers 14 cantilever mounted on the support ring 13 and an unwind arm 15. The packing rollers 14 are mounted angularly apart on the support ring 13 and rotatably about respective longitudinal axes, in parallel with respect to the packing X axis, and extend from the support ring 13 in the direction of travel A.

The unwind arm 15 has a first end 15a, rotatably fixed to the support ring 13 around a respective Y-axis, and a second end 15b that supports one or more unwind rollers 16, 17, which rotate around the axes. respective longitudinal and arranged to rest on the film part 51 and guide it towards the products 100 during its packaging, the unwinding arm 15 being movable in order to approach and / or separate the unwinding roller or rollers 16, 17 with respect to said 100 products during packing.

In the embodiment shown, the second end 15b of the unwind arm 15 is provided with a pair of unwind rollers 16, 17 arranged to rest on opposite sides of the film part 51 when the initial fin 51a of the film part 51 is held and supported by the first means 4 for holding the support means 3 in the closed position B1.

The support ring 13 is rotatably supported by machine frame means (not shown) and rotates by respective drive means, comprising, for example, a rotating electric motor.

As explained in more detail below in the description, when the support ring 13 rotates around the packing X-axis in a first packing stage, it unwinds and moves the film part 51 from the supply unit 30 and, at the same time, by means of the unwinding arm 15, it wraps the product group 100 with a first section of the film part 51, provided with the initial flap 51a, and wraps the packing rollers 14 with a second section of the part 51 of the film, provided with a terminal flap 51b. In a second packing stage, by means of the unwinding arm 15, the support ring 13 rotates and wraps the product group 100 with the second section of the film part 51, displaced and unrolled by the packing rollers 14, for the purpose to complete and form package 200.

As shown in Figures 8, 13 and 14, the packing means 12 may be arranged along an orthogonal direction with respect to the support plane M in different working positions according to the dimensions of the products 100 to be packed and so that the latter are substantially centered with respect to the X-axis of packaging in order to allow optimum packaging with the film part 51.

In the case of products with large dimensions, for example, water bottles 100 (Figure 8), the packing means 12 are arranged so that the turning axis X is arranged at a first distance H1 from the support plane M formed by the support means 3 and the slide plane 25. The first distance H1 is larger than a second arrangement distance H2 of the turning axis X of the packing means 12 with products 100 '' with an intermediate size (Figure 13). In turn, the second distance H2 is larger than a third arrangement distance H3 of the packing axis X of the packing means 12 with containers 100 '' 'with a small size (Figure 14).

Each packing roller 14 includes a respective cylindrical element having a length equal to or larger than the width of the film 50 and fixed to the support ring 13 so as to freely rotate about the respective longitudinal axis, in parallel with respect to the X axis packing

Also, the unwinding rollers 16, 17 comprise respective cylindrical elements having a length equal to or larger than the width of the film 50. At least the first unwinding roller 16 is externally coated with a layer of elastomeric material or similar for the purpose. if it is supported with friction on the film part 51 and, therefore, can withstand it when wrapping the product group 100, thereby guaranteeing adequate packing tension. The first unwinding roller 16 is also provided with an internal clutch in order to obtain an adjustable resistance to rotation, which allows the film to be kept under tension or traction when wrapping the product group.

The unwinding arm 15 is movable between a first operating position E1, where the unwinding rollers 16, 17 are further separated from the product group 100 to divert the film part 51 towards the group, specifically, in the first packing stage, and a second operating position E2, wherein the unwinding rollers 16, 17 are closer to the product group 100 to divert at least the terminal flap 51b of the film part 51 into the products. To this end, the unwind arm 15 includes brush means 18 fixed to the second end 15b and arranged to rest on the film part 51, specifically, the terminal flap 51b, and adhere it to the product group 100 at the end of the packaging .

The packing means 12 further includes a drive ring 19 that is adjacent and coaxial with with respect to the support ring 13 and which can be rotatably driven around the packing X axis separately and independently with respect to the support ring 13. The drive ring 19 is rotatably supported by the machine frame means and rotates by respective drive means comprising, for example, a rotating electric motor. The drive ring 19 is connected to the first end 15a of the unwind arm 15 in order to rotate the latter at least between the first operating position E1 and the second operating position E2. More precisely, the drive ring 19 has a seat 57 arranged to receive a first guide shaft 58 fixed to a movable part 59 of the unwind arm 15 extending from the second end 15b. Alternatively, the drive ring 19 may include a cam profile suitable for resting on the guide shaft 58 and moving it.

As explained in more detail below in the description, the relative rotation of the drive ring 19 with respect to the support ring 13 causes the unwinding arm 15 to rotate around the respective rotation Y axis between the first position E1 of operation and the second operating position E2.

The unwind arm 15 comprises a first unwind roller 16 rotatably mounted about a respective axis of rotation at the second end 15b and a second unwind roller 17 rotatably mounted about a respective axis of rotation at the second end 15b and movable between a supporting position F1, where it is supported on the first unwinding roller 16 to contact and move the film part 51, and a separating position F2, where the second unwinding roller 17 is separated from the first unwinding roller 16 to allow, in the initial adjustment stage, that the insertion arm 11 transfer the initial flap 51a to the support means 3 and that the first roller 16 contacts the film part 51. Specifically, the unwind arm 15 is provided with a drive lever 20 rotatably fixed to the first end 15a of said unwind arm 15 and which rotatably supports the second unwind roller 17. The drive lever 20 is actuated by the drive ring 19 in order to move the second unwind roller 17 between the support position F1 and the separation position F2. More precisely, the drive lever 20 has a second guide shaft 23 where a drive element 24 of the drive ring 19 is supported (in the first operating position E1 of the unwind arm). The drive element 24 has a support wall that is in contact with the second guide shaft 23; in this way, a relative rotation of the drive ring 19 with respect to the support ring 13 causes the second guide shaft 23 to slide into the support wall and, therefore, the partial turn of the drive lever 20.

The insertion arm 11 includes a first terminal part 11a rotatably fixed to the frame means of the machine 1 and a second terminal part 11b provided with second fastening means 21 suitable for holding and supporting the initial fin 51a of the film part 51 .

The insertion arm 11 can be rotatably actuated between a holding position G1, where it is adjacent to said supply unit 30, specifically, for the purpose of holding the initial fin 51a, and a transfer position G2, in wherein the second fastening means 21 of the insertion arm 11 are adjacent and are oriented towards the first fastening means 4 of the support means 3 in order to transfer the initial fin 51a to said first fastening means 4. To this end, the transfer arm 11 includes an insertion bar 28 arranged in the second clamping means 21 and movable along the insertion arm 11 in order to insert the initial flap 51a between the two support elements 4 arranged in the opening position B2. The initial fin 51a is held inside the support elements 4 until they are moved to the closed position B1 by an air jet emitted by the insertion bar 28.

The insertion bar 28 is moved linearly by a respective linear drive device, for example, a pneumatic cylinder, of known type and not shown in the figures.

In the embodiment shown in the figures, the second fastening means include tweezers 21 provided with a fixed element 21a and a mobile element 21b, the latter moving by means of a respective linear drive device 29, for example, a pneumatic cylinder, between a supporting position in the fixed element 21a for holding and locking the initial fin 51a of the film part 51 and a separate position of said fixed element 21a to allow the release of the initial fin 51a and / or the passage of the film 50.

First blowing means 22 fixed to a frame of the packaging machine 1 are used for the purpose of emitting a jet of compressed air capable of separating the film 50 from the tweezers 21 during the return movement of the insertion arm 11 of the position G2 transfer to the holding position G1 (figure 24).

Referring specifically to Figure 3, the supply unit 30 comprises support and movement means 31, 31 'for supporting and rotating at least one coil 55 of film 50, means 32 of unwind to unwind and previously stretch said unwound film 50 from the reel 55 and cutting means 80 to make a separation line in said film 50 that is transverse with respect to a direction of unwinding of the film and arranged to separate part 51 of film, which comes out of the unwinding means 32, of the film 50 unwound from the coil 55.

The unwinding means 32 specifically comprise a pair of motorized pre-stretching rollers 33, 34, suitable for unwinding and previously stretching the film 50, first return rollers 35 for diverting the film 50 towards the pre-stretching rollers 33, 34 and a pair of motorized traction rollers 36 arranged to dispense the film portion 51 to the packing unit 10 and to hold the stretch of film between said traction rollers and the pre-stretching rollers 33, 34.

The pre-stretching rollers include a first fast roller 33 disposed downstream with respect to a second slow roller 34 to stretch or lengthen the film 50 a predetermined percentage (depending on the difference in rotation speed between the two rollers). The pre-stretching rollers 33, 34 rotate by at least one motor. Second return rollers 37 are used upstream with respect to the pre-stretching rollers and form means to control the tension and supply of the film 50 during packaging. Alternatively, it is possible to adjust and control the tension of the film by load cells associated with the return rollers or by measuring the operating parameters of the motors that drive the pre-stretching rollers 33, 34 and the traction rollers 36.

The cutting means 80 are arranged between the two traction rollers 36 and a return roller 35, downstream with respect to the pre-stretching rollers 33, 34, to execute a plurality of cuts in the film 50, specifically, a plurality of perforations that form a separation line.

To this end, the cutting means 80 comprise a cutting roller 81 which rotates about a respective longitudinal axis and provided with a plurality of mutually separated cutting elements along said longitudinal axis and arranged to cut and perforate the film 50 in order to make the transverse separation line, specifically, orthogonal with respect to a winding direction of the film 50. The cutting means 80 also comprise an opposite rotating roller 82, provided with a longitudinal cavity arranged to receive the elements Cutting the cutting roller. The opposite roller 82 rotates synchronously with the cutting roller 81, both rollers rotating by the same motor.

Detector means are used to measure the length of the film portion 51 dispensed by the supply unit 3. Said detector means comprise, for example, a transducer or angular encoder that measures the number of turns of the traction rollers 36.

As explained in more detail below in the description, during the packaging of the product group 100, when the film part 51 has completely left the delivery unit 30, specifically, when the separation line has passed the traction rollers 36, the latter and the pre-stretching rollers 33, 34 stop and the second fastening means 21 of the insertion arm 11 are closed in order to block the film 50. In this way, the film part 51 displaced by means of the packing means 12, specifically, by rotating the support ring 13, it is separated along the line of separation of the film 50 from the coil 55. Due to the traction to which it is subjected the film 50, the plastic material weakened by the cuts made by the cutting means 80 is fractured precisely and cleanly along a transverse line.

The film fin supported by the tweezers 21 forms the initial fin 51a of the subsequent film part 51 intended to pack a respective group of products 100.

Second blowing means 38 are arranged downstream with respect to the two traction rollers 36 for blowing the film flap generated from the fracture and supported by the second fastening means 21 towards the insertion arm 11.

In the embodiment shown, the support and movement means include first support and movement means 31 and second support and movement means 31 'which are arranged to support and rotate reels 55 of film 50 and respective attachment means 85, of known type and not shown in detail, for attaching a front fin of a new coil 55 to a rear fin of a nearly exhausted coil 55. In this way, the replacement of the coils 55 can occur without it being necessary to stop the packing machine 1.

Referring specifically to FIG. 1, the packaging machine 1 of the invention includes means 70 for narrowing the film part 51 leaving the supply unit 30. The narrowing means 70 comprise a pair of narrowing rollers 71 that are mounted in parallel and opposite each other, free to rotate about respective lengths, substantially orthogonally with respect to the film part 51. The narrowing rollers 71 rest on opposite longitudinal edges of the film part 51 and fold them, specifically, partially winding them, in order to confer a greater mechanical resistance to the film part and the packaging made around the product group 100.

It is possible to adjust the transverse distance between the two narrowing rollers 71 by suitable drive means according to the width of the film 50 and / or the extent of the winding / bending to be executed at the longitudinal edges of the film part 51.

The operation of the packaging machine 1 of the invention comprises moving a group of products 100 to be packaged in a package 200 along the first conveyor means 2. The product group 100 is pushed in the slide plane 25 along the direction of travel A by means of the pusher cross members 26 and is supported laterally by the second guide means 6. Next to the packing unit 10, the product group 100 is transferred from the slide plane 25 to the support means 3, specifically, the products 100 are pushed into the support plane M formed by the walls 41 of the elements 4 support. The latter are arranged in the closed position B1, since they support and block the initial flap 51a of the film part 51 that will wrap the products 100.

Once the product group 100 has reached the inside of the packing unit 10 in the correct packing position, the packing means 12 can be activated in order to start packing with the film.

The position of the packing means 12 with respect to the support plane M (distance H1, H2, H3) is adjusted preventively according to the dimensions of the products 100 (Figures 8, 13, 14). Specifically, the support ring 13 and the drive ring 19 move vertically, orthogonally with respect to the support plane M.

The packaging process (shown in Figures 15 to 24 with other products or containers 100 'of small size, for example, a can) comprises a first stage where the support ring 13, when rotating about the packaging X axis, unwind and move the film part 50 from the supply unit 30 and wrap the product group 100 with a first section of said film part 51 provided with the initial flap 51a (locked by the support elements 4) and wrap the rollers 14 with a second section of said film part 51 provided with the terminal flap 51b (Figures 15 and 16). The unwinding arm 15 is arranged in the first operating position E1 to divert the film part 51 towards the product group 100. To this end, the drive ring 19 rotates together with the support ring 3 and at the same speed as the same.

The film part 51 envelops the product group 100 and the support elements 4, specifically, rests on the first tapes 42 along the operating section T.

In this way, the film part 41 is separated from the film 50 thanks to the separation line carried out by the cutting means 80. More precisely, while the film part 51 wraps the packing rollers 14, thanks to the rotation of the support ring 13, the film 50 is supported by the second securing means 21 of the insertion arm 11, with the rollers 36 of traction locked. In this way, the film 50 is subjected to traction and is fractured along the separation line in a clean manner, allowing the separation of the film part 51, which can completely wrap the product group 100 (Figure 17).

In a second packing stage, the support ring 13, when rotating about the packing X-axis, wraps with the second section of the film part 51, displaced and unwound from the packing rollers 14, the product group 100 a effects of completing and forming the package 200. In this second packing stage, the unwinding arm 15 moves to the operating position E2, where the brush means 18 are supported on the film part 51 and push it, of specifically, in the terminal flap 51b, to adhere to the product group 100 (Figures 18-21). The unwind arm 15 moves to the second operating position E2 thanks to the relative rotation of the drive ring 19 with respect to the support ring 13.

It should be noted that the length of the film part 51 is selected such that the terminal flap 51a is applied to the base of the package 200, that is, substantially superimposed with respect to the initial fin 51a. The correct and desired length of the film part 51 is verified by means of detecting the supply unit 3, which detect the unwinding of the film part, for example, when leaving the dispensing rollers 36.

The package 200 is carried out with a plurality of film turns, the different turns adhering to the products 100 and with each other thanks to the adhesive capacity of said film, preferably made of a plastic material containing a suitable adhesive. The adhesive capacity of the film ensures that the terminal flap 51b remains attached to the package 200 at the end of the packaging. The brush means 18 allow the film to adhere to the products 100 optimally. The compactness of the packaging is also guaranteed by the elastic return of the film 50 subject to a stretch or extension prior to leaving the unit of supply by means of rollers 33, 34 of previous stretching. In fact, once arranged and wrapped around the products 100, the film 50 tends to contract and return to the original length, thus stabilizing and compacting the package 200.

It should be noted that, because the length of the film part 51 is previously adjusted, defined according to the dimensions and / or shape of the products 100, and because it is possible to arrange the initial fin 51a and the terminal fin 51b in positions defined with respect to the product group 100 (at the base), it is possible to use a film 50 made of extendable plastic material with prints, writings, drawings, decorations or the like, which will be arranged in the package 200 in the desired positions , for example, on the side walls or on the top.

Once the packaging is finished, the guide means 5 move from the release position D2 to the holding position D1 to rest on the package 200 when leaving the packing unit 10 and supporting it laterally. In fact, the package 200 is pushed along the direction of travel A outside the packing unit 10 by the subsequent product group 100 arranged upstream and, in turn, pushed and moved by a respective pusher cross member 26 ( figure 6).

The support stems 61 of the guide means 5 enter between the guide projections 67, 67 'of the pair of side panels 65 of the second guide means 6.

Therefore, the package 200 is transferred in the second conveyor means 7. The first movement belts 42 of the support elements 4 are rotatably actuated to allow the package 200 to be separated from the support elements. Specifically, the first tapes 42 are driven to move in the operating section T along the direction of travel A in conjunction with the package 200, thereby allowing the progressive separation of the film that surrounds said second tapes 42.

Also, the second movable belts 62 of the support rods 61 of the guide means 5 are actuated in order to move the package 200 in the direction A of travel. At the same time, the guide means 5 themselves move from the holding position D1 to the releasing position D2. In this way, the package 200 is easily transferred from the support means 3 inside the packing unit 10 to the second conveyor means 7, separating from the support elements 4.

The second conveyor means 7 transport the package 200 leaving the packing machine 1 along the direction A of travel.

The product group 100 that has pushed the package 200 out of the packing unit 10 is arranged in the support means 3 to be packed.

At the end of the packing and before the transfer of the package 200 of the support means 3 to the second conveyor means 7, the support elements 4 are arranged in the opening position B2 to allow the release of the initial fin 51a and, therefore, of the package 200, and the subsequent insertion of the initial flap 51a of a portion 51 of subsequent film dispensed by the supply unit 30 to pack the subsequent product group 100.

Therefore, prior to packaging, an initial adjustment step of the film part 51 is used where the packing arm 15 returns to the first operating position E1 and the second unwinding roller 17 moves to the F2 position of separation, that is, separated from the first unwinding roller 16 in order to allow the passage of the second securing means 21 of the insertion arm 11. In fact, the second fastening means 21 are closed to support the initial flap 51a of a subsequent film part 51 that will be unwound and separated from the film 50. In this way, the insertion arm 11 moves from the G1 position of fastened to the transfer position G2, where it is disposed adjacent to the support means 3 for the purpose of transferring the initial fin 51a to the support means (figures 21-24). More precisely, in the transfer position G2 of the insertion arm 11, said second fastening means 21 are oriented towards the support elements 4 mutually spaced in the opening position B2 to allow the initial flap 51a to be inserted inside. The initial flap, which is bent by means of the second blowing means 38 around the insertion bar 28 of the insertion arm 11, after fracturing the film 50 and separating the part 51 of the previous film, is pushed between the two elements 4 of support by means of the insertion bar 28, which moves to approximate the support means 3, and by means of a jet of compressed air dispensed from the insertion bar 28 itself (figure 4). While the air jet is dispensed, the two support elements 4 move to the closed position B1 in order to block and support the initial fin 51a. At the same time, the insertion bar 28 returns to a respective retracted position, where it is further separated from the support means 3.

In this way, the insertion arm 11 returns to the holding position G1, with the second holding means 21 in the opening position to allow the passage of the film 50 during packing. At the same time, the second unwinding roller 17 moves to the supporting position F1 in order to attach the film part 51 to the first unwind roller 16. In this way, the packing means 12 can be activated to wrap the product group 100 with the film part 51 in order to form the package 200.

It should be noted that during the operation of the packaging machine 1 it would be possible to easily replace a reel of almost exhausted film 55 with a new reel of film without it being necessary to stop the operation thanks to the joining means 85 of the supply unit 30. In fact, the joining means allow the front flap of the new coil to be attached to the rear flap of the almost exhausted coil 55. It is possible to remove the almost exhausted coil from the supply unit 30 and replace it with a new coil during operation of the packaging machine, which uses the other coil.

Therefore, the packaging machine 1 has a high productive autonomy, since it is not limited by the replacement of the film reels 55.

By arranging the film reel 55 on the machine side, inside the supply unit 30, there is also a considerable reduction of the rotating masses of the packing means 12 (support ring 13 and drive ring 19) with respect to known packaging apparatus provided with a rotating support ring, this allows increasing the performance of the packaging machine (rotating speed, acceleration) and / or reducing the energy consumption of the motors used to rotate the rings. The smaller doughs that rotate through the rings also allow reducing the structural tensions of the packaging unit, increasing its useful life and reducing the risk of damage.

Therefore, thanks to the packaging machine 1 of the invention, it is possible to efficiently and efficiently pack product groups 100 in packages 200 using a film 50 made of cold-stretch plastic material.

In addition, the packaging machine allows to pack groups of products 100 using a printed film 50, that is, provided with writings, drawings, decorations or the like. In fact, the film portion 50 having a predetermined length can be arranged accurately and reproducibly around the products 100, allowing this to arrange the writings, drawings, decorations or the like in the desired positions in the package 200.

The packaging machine 1 of the invention is versatile and flexible, since it allows packages of products having different sizes and dimensions to be packaged in a precise and efficient manner, without complicated and difficult adjustment and / or regulation operations being necessary. . In fact, it is sufficient to modify the position of the packing means 12 (ie the position of the support ring 13 and the drive ring 19) with respect to the support plane M in order to arrange the products 100 to be packed in the packaging. optimal packing position.

Figure 25 shows a variant of the packaging machine 1 of the invention that differs from the embodiment described above by the insertion arm 11, which is provided with second clamping means 121 comprising a clamping bar 122 having an elongated shape and transverse with respect to the film 50 and provided with suitable air suction means to support the initial flap 51a of the film part 51 by depression or suction. For example, the clamping bar 122 has a quadrangular cross-section and has a support wall for the film where a plurality of openings of the suction means are made in fluid connection with a suction unit, for example, a pump vacuum, packing machine 1. The holding bar 122 is movably mounted on the insertion arm 121 and is linearly operated along an almost orthogonal direction with respect to the film 50, between an extended position K1 and a retracted position K2, by means of a device 129 respective linear drive, for example, a pneumatic cylinder.

With the insertion arm 11 in the holding position G1, the holding bar 122 moves to the extended position K1 to support the film 50 and support it. To this end, the holding bar 122 pushes the film 50 against a fixed elongate opposite element 163 of the supply unit 30. In the retracted position K2, the holding bar 122 allows free movement of the film 50 and allows the insertion arm 11 to rotate between the holding position G1 and the transfer position G2.

With the insertion arm 11 in the transfer position G2, the holding bar 122 moves to the extended position K1 in order to transfer the initial flap 51a to the first securing means 4 of the support means 3. To this end, the suction of air through the openings of the holding bar 122 stops and, through them, compressed air is emitted, which pushes said initial fin 51a against the first holding means 4, so more specifically, inside the cavity or groove formed by the two support elements 4 arranged in the opening position B2.

Once the initial flap 51a is secured, moving the support elements 4 to the closing position B1, the clamping bar 122 can return to the retracted position K2 in order to allow the insertion arm 11 to rotate to the holding position G1 .

Figures 26 and 27 show another variant of the packaging machine 1 of the invention that differs from the embodiment of figures 1 to 25 by the insertion arm 11, the support means 103 and the corresponding first fastening means 104.

The insertion arm 11 is the one provided with second fastening means 121 with suction means described above, and shown in Figure 25.

The support means 103 include first fastening means formed by a single support element 104 with a substantially elongated shape in the direction of travel A and comprising a support wall 141, which forms the support plane M for the product group 100, and air suction means 40, arranged to absorb and support by depression the initial fin 51a of the film part 51 during packaging. The suction means 40 comprise a plurality of respective openings or grooves 146 made and which exit at a base wall 148 of the support element 104, opposite the support wall 141, and in fluid connection with a suction unit, by For example, a vacuum pump, from the packing machine 1. More precisely, the suction means comprise a conduit 147 made inside the support element 4, which extends in the direction of travel A and which is provided with through openings 146. The conduit 147 is in fluid connection with the suction unit.

The support means 103 further include a pair of first movable belts 142 associated with the support element 104, which are flexible, endless and arranged to be supported thereon along respective operating sections T part 51 of film during packing. The first tapes 142 are driven to move, in the respective operating sections T, along the direction of travel A, together with the package 200 leaving the packing unit 10, in order to allow the package 200 to be separate from support element 4. Each first belt 142 wraps a plurality of pulleys 143, 144, 145 which rotate about respective axes that are orthogonal with respect to the support wall 141, that is, with respect to the support plane M. Each first tape 142 has a support surface that is almost orthogonal with respect to the support wall 141 and that can be contacted in the operating section T with the film portion 51 that surrounds the product group 100.

In the operating sections T, the first ribbons 142 exit the support element 4 on their opposite sides in order to rest on the film part 51.

Inside the support element 4, each first belt 142 wraps a respective first pulley 143, which rotates by means of a respective first motor, a pair of respective second return pulleys 144 and a third respective return pulley 145, the pulleys 144 being , 145 rotating and free return.

The operation of this variant of packaging machine 1 of the invention is substantially identical to that of the embodiment described above and shown in Figures 1-24, differing only by the diverse functionality of the second means 121 for securing the insertion arm 11 and the first means 104 for securing the support means 103.

During packing, the insertion arm 11 is arranged in the holding position G1, the holding bar 122 moves to the extended position K1 in order to rest on the film 50 and support it when the latter is stopped to allow the separation of the film part 51 along the separation line, said film part 51 being displaced by the packing means 12 when rotated. In this way, the film flap generated by separation, which corresponds to the initial film flap of the subsequent film portion (still connected to the film 50 to be unwound from the reel 55), is supported and locked by the seconds fastening means 121. Specifically, the holding bar 122 pushes the film 50 against the opposite element 163 of the supply unit 30 and moves to the retracted position K2 after holding the film 50 by depression or suction.

At the end of the packaging, and specifically at a stage of adjustment of a subsequent packaging, the insertion arm 11 moves to the transfer position G2 where the holding bar 122 moves to the extended position K1 to rest on the lower wall 148 of the support element 104 for the purpose of transferring and arranging the initial flap 51a of the film part 51 in the suction means 40 of the support element 104. To this end, the suction of air through the openings of the clamping bar 122 stops and compressed air is emitted that pushes the initial fin 51a towards the respective openings of the suction means 40 of the support element 104, where the air suction is activated in order to firmly support the initial fin 51a of the film part 51.

Thus, the holding bar 122 returns to the retracted position K2 to allow the insertion arm 11 to rotate from the transfer position G2 to the holding position G1.

Referring to Figures 28 and 29, another variant of the packing machine 1 of the invention is shown which differs from the embodiment described above and shown in Figures 1 to 25 by the packing means 12 of the packing unit 10, wherein the packing rollers 114, cantilevered mounted on the support ring 13, and the first unwinding roller 116, cantilevered mounted on the unwind arm 15, are motorized, that is, rotate by respective drive means about the respective longitudinal axes, which are parallel with respect to the X axis of packaging. More precisely, first drive means 160 are arranged to rotate packing rollers 114 and first unwind roller 116 and second drive means 150 are arranged to rotate support ring 13, rotatably supported by means 9 of frame.

The second drive means 150 comprise, for example, a first rotating electric motor 151, which rotates a first transmission belt 152 that surrounds the support ring 13 through a first transmission pulley 153 and a first return pulley 154 .

In the embodiment shown in the figures, the first drive means 160 comprise a transmission ring 161 that is mounted on the support ring 13, free to rotate about the packing X axis, by a plurality of support rollers 162. A second rotating electric motor 163 rotates a second transmission belt 166 that wraps the transmission ring 161 through a second transmission pulley 164 and a second return pulley 165. A third drive belt 167, which meshes with a first driven pulley 168 rotatably fixed to the frame means 9 and rotates it, wraps around the ring. To the first driven pulley 168 a third transmission pulley 169 is coaxially fixed which, through a fourth transmission belt 171, rotates one of the unwinding rollers 114 and a second driven pulley 172 fixed to the unwinding arm 15 and which drives a fourth transmission pulley 173 coaxially fixed thereto. The fourth drive pulley 173 rotates the first unwind roller 116 of the unwind arm 5 through a fifth drive belt 174. A sixth transmission belt 175 wraps and connects the packing roller 114, driven by the fourth transmission belt 171, to the rest of the packing rollers 114 (and to a third return pulley 176). Preferably, the transmission belts and pulleys are of the toothed type in order to guarantee a precise and regular movement transmission.

The packing rollers 114 and the first unwinding roller comprise respective crowns (not shown) wrapped and engaged by the respective drive belts.

In this way, the first driving means 160 of the packaging machine of the invention allow the packing rollers 114 and the unwinding roller 116 to rotate independently and autonomously with respect to the support ring 13, that is, independently and autonomous with respect to the packing speed of the film part 51 around the products 100. The packing rollers 114 and the first unwinding roller 116 rotate so as to facilitate the unwinding of the film part 51 from the supply unit 3 and the contextual wrapping of the products 100 with said part 51. Furthermore, by adhering to the film part 51 and its movement during packaging, the packing rollers 114 and, specifically, the first roller 116 unwinding (in combination with the second unwinding roller 117) also allow the tension of the film to be regulated, especially together with the products 100.

A variant, not shown in the figures, is disclosed in which the packing rollers 14 can rotate freely, that is, they rotate freely and only the first packing roller 116 rotates around its own longitudinal axis by means of the first means 160 drive.

Figure 30 shows another variant of the packaging machine 1 of the invention that differs from the embodiment described above and shown in Figures 1 to 25 by the packing means 12 of the packing unit 10, which include one or more tapes 130 of support which are arranged, during the rotation of the support ring 13 around the packing axis X, to rest on the packing rollers 14 and wrap them, said rollers being arranged progressively in an upper arc 13a of said support ring 13 arranged on the products 100, in order to keep the film part 51 strictly adherent to the packing rollers 14 and, specifically, to prevent the separation of the terminal flap 51b from the part 51 after the latter leaves the unit 30 of supply. Preferably, a plurality of packing tapes 130 are disclosed that are arranged in parallel and spaced apart from each other along the direction of the packing X axis in order to adhere the film on the packing rollers 14 across the entire width of the movie. Each support belt 130 is endless and wraps two lower return pulleys 131 and two upper return pulleys 132, fixed to the frame means 9 of the packing machine 1, to adhere to the packing rollers 14 in the upper arc 13a of said support ring 13. The support tapes 130 are moved by the packing rollers 14 in the same direction as the direction of rotation of the support ring 13, that is, the packing direction of the film part 51 around the products 100.

Referring to Figure 31, another additional variant of the packaging machine 1 of the invention is disclosed which differs from the embodiment described above by the unwinding means 32 and the cutting means 80 of the supply unit 30 and by the insertion arm 11.

In this variant of the machine, the unwinding means 32 comprise a pair of pre-stretching rollers 33, 34, motorized and capable of unrolling and previously stretching the film 50, at least one return roller 35 to deflect the film 50 from the coil towards the stretching rollers 33, 34 and a pair of traction rollers 136, 137 arranged downstream with respect to pre-stretching rollers 33, 34 for dispensing the film portion 51 to the packing unit 10.

The pre-stretch rollers comprise a first rapid pre-stretch roller 33 disposed downstream with respect to a second slow pre-stretch roller 34 to stretch or extend the film 50 a predetermined percentage (according to the difference in rotation speed between the two rollers ). The pre-stretching rollers 33, 34 rotate by means of at least one motor and in them respective support rollers 133 and 134 are supported, for example, mounted on an elastic or adjustable support, not shown, which ensure the correct adhesion of the film 50 to said pre-stretching rollers 33, 34. The traction rollers comprise a first motorized traction roller 136 and a second free traction roller 137 mounted on a respective oscillating arm 138 and, therefore, movable between an operating position, where the second traction roller 137 presses the film 50 against the first traction roller 136 to allow the latter to tension the stretch of film between the first pre-stretch roller 33 and the traction rollers 136, 137, and a separation position, wherein said second roller 137 of traction is separated from the first traction roller 136 in order to allow rotation of the insertion arm 11, as will be explained in more detail below in the description. The cutting means 80 are arranged between the two traction rollers 136, 137 and the first pre-stretching roller 33 and comprise a cutting roller 181 that rotates about a respective axis that is longitudinal and transverse with respect to the unwinding direction. of the movie; The cutting roller 181 is provided with a blade suitable for cutting or shearing the film 50 transversely in order to obtain the film portion 51 with a suitable length.

The free end of the insertion arm 11 is provided with second holding means 221 comprising a holding bar 222 that has an elongated and transverse shape with respect to the film 50 and provided with air suction means capable of supporting by means of depression or suction the initial fin 51a of the film part 51 generated as a result of the cut executed by the cutting roller 81. For example, the holding bar 222 has a quadrangular cross-section and has a support wall for the film 50 where a plurality of openings of the suction means are made in fluid connection with a suction unit, for example, a vacuum pump, packing machine 1. The clamping bar 222 also has an opposite part 222a which has a shape that receives the section of sheared film by means of the cutting roller 181.

It should be noted that the cut forms the terminal flap 51b of the film part 51 that surrounds the load 100 and the initial fin 51a of the subsequent part 51 of the film 50 that will wrap a subsequent group of products 100, said initial fin 51a being supported by means of the second fastening means 221 of the insertion arm 11, arranged in the holding position G1.

In this variant, the insertion arm 11 also includes an insertion blade 228 disposed in the second fastening and movable means 221 along the insertion arm 11 in order to insert the initial flap 51a of part 51 between the two elements 4 for supporting the first fastening means arranged in the opening position B2, when the insertion arm 11 is arranged in the transfer position G2 (broken line in Figure 31).

It should be noted that in the variant shown the support elements 4 of the support means 3 (which also function as the first fastening means) do not include mobile support tapes for the film. The insert blade 228 is moved linearly by a respective linear drive device 229, for example, a pneumatic cylinder of known type.

In order to allow rotation of the insertion arm 11 between the holding position G1 and the transfer position G2 to transfer the initial flap 51a, supported by the second holding means 221, to the first holding means 4, the second roller 137 of traction is moved by rotating the oscillating arm 138 corresponding to the separation position, where the second traction roller 137 is separated from the first traction roller 136 and does not interfere with the holding bar 222 and the arm insertion blade 222 11 insertion.

Referring to Figures 32 to 34, a variant of the packaging machine 1 of the invention is shown which differs from the embodiment described above and shown in Figures 1 to 25 by the different means 60 for containing products 100 and by the fact that it does not include guide means arranged to rest on the side walls of the products and guide the latter when leaving the packing unit 10.

Also in this variant, the products 100, which form the group or load to be packed, are arranged in the support plane M formed by the support means 3 and the conveyor means 2, 7, although because they are unstable , they must be supported by the containment means 60 when entering the packing unit 10 and during the packing stage. The containment means include a pair of side panels 261 that rest on the side walls of the products 100 inside the packing unit 10. The transverse position, that is, along an orthogonal direction with respect to the direction of travel A of the products, can be adjusted according to the dimensions of the products 100 or the package 200 formed. To this end, the two side panels 261 are mounted on a side guide 263 along which they can be moved and thus locked accordingly.

Each side panel 261 comprises a terminal edge 261a adjacent to the second conveyor means 7 (arranged downstream with respect to the packing unit 10 in order to support and move the products along the direction of travel A and leaving the packing machine 1) to which a respective support door 262 is rotatably fixed, which is movable to block the products 100 that move along the direction of travel A, specifically, during the packing. More precisely, each support door 262 is fixed to the end edge 261a of the respective side panel 261 to rotate about a substantially vertical axis, between a closed position, where the support door is turned towards the opposite side panel 261 in order to block the products 100 that move along the direction of travel A, and an opening position, where the support door is almost aligned with the respective side panel 261 in order to allow the products to pass 100 that move along the direction of travel A and, therefore, leaving the packing unit 10. A respective drive device 264, for example, of pneumatic type, is arranged to rotate each support door 262 by means of lever means 265.

In this variant of the packaging machine 1, the first fastening means 4 are integrated with the support means 3 and comprise two support elements 4 that are adjacent and opposite and form the support plane M. The support elements 4 are moved by respective linear drive devices 266, for example, pneumatic cylinders or linear electric motors, transversely with respect to the direction A of travel, between the closing position B1 and the opening position B2.

Referring specifically to FIG. 34, the packaging machine 1 includes additional pusher means 270 that act upstream with respect to the group of products 100 partially introduced into the packaging unit 10 by means of the pusher means 26 (pusher crossbars) of the first means 2 of conveyor. The additional pusher means 270 push the products 100, slidably supported by the support walls 41 of the support elements 4 and by the side panels 261, until they are compacted against the support doors 262 arranged in the closed position which, from In this way, they form a fixed reference line for the next packaging of the products 100 with the film 50.

The additional pusher means 270 comprise a pusher plate 271 suitable for resting on the side walls of the products 100 further apart from the support doors 262. The pusher plate 271 is supported by a lever 272 of shaped support and which is moved by means of actuation 273, 274 to separate from the products 100 and the packing unit 10, after compaction, without interfering with a group of products subsequent 100 that travels along the support means 3. The drive means include, for example, a first linear drive device 273 that linearly supports and moves the support lever 272 along a transverse direction relative to the direction of travel A and a second linear drive device 274 that it supports and moves the first linear drive device 273 in parallel with respect to the direction A of travel. By properly controlling the two linear drive devices 273, 274 it is possible to move the support lever 272 and, therefore, the pusher plate 271, with a suitable desired interpolated path, specifically, when leaving the unit 10 of packaging.

The operation of this variant of packaging machine 1 allows the group of products 100 of the first conveyor means 2 to be transferred to the support means 3 of the packing unit 10 by means of the pusher cross members 26. The additional pusher means 270 function for this purpose. of compacting and pushing the products 100 inside the packing unit 10 against the support doors 262 of the containment means 60, arranged in the closed position. The side panels 261 keep the products 100 (for example, bottles) in a stable and vertical position during the transfer in the support means 3 and during the packaging with the film part 51. Before starting the packing, the pusher plate 271 of the additional pusher means 270 is separated from the products 100 and removed from the packaging unit 10 so as not to interfere with the film being unwound.

During operation of the packing means 12 the film part 51 wraps the product group 100 and also wraps the side panels 261 and the support doors 262. However, thanks to the elasticity of the film 50 and the flat and elongated shape of the side panels 261 and the support doors 262, it is possible to easily separate the package 200 from the containment means 60 (with the support doors 262 arranged in the opening position) at the end of the packaging and transfer the package of the support means 3 to the second conveyor means 7. Specifically, the products 100 packed with the film are pushed out of the packing unit 10 along the direction of travel A by a group of incoming products 100 to be packed, arranged upstream and, in turn, pushed and moved by means of a respective pusher cross member 26.

Figure 35 shows another embodiment of the packaging machine 1 of the invention that differs from the embodiment described above and shown in Figure 1 by the fact that it includes supply conveyor means 208 that are arranged in parallel and aligned with the first conveyor means 2 along the direction of travel A, and an additional packing unit 110 disposed downstream with respect to the packing unit 10 for wrapping the package 200 with a tape or list 250 made of plastic film for this purpose of forming at least one ring for the user to hold and transport.

The additional packing unit 210 is substantially identical to the packing unit 10, with packing rollers and holding rollers of the packing means 212 with a reduced length, reducing the width of the tape 250.

A third conveyor means 202 is disposed between the packing unit 10 and additional support means 203 arranged upstream with respect to the additional packing unit 210 for the purpose of supporting the package 200 and receiving and blocking a respective initial flap of the belt 250. The additional packing unit 210 is fed by an additional supply unit 230 that is substantially similar to the supply unit 30, in this case, without the pre-stretching rollers, which are not necessary to lengthen the tape or list 251 .

The tape 250 wraps the package 200 one or more times in order to form a solid and resistant ring for lifting and transporting it and is fixed to the package film by welding and / or glue. Preferably, the tape is welded to a lower part of the package 200 through known means, not shown, and at two or more points on the side walls of the package.

Claims (7)

1. Packing machine for packing product groups (100) with an extendable plastic film (50) for the purpose of forming packages (200), comprising: - first conveyor means (2) for supporting and moving a group of products (100) along a direction (A) of movement inside the packaging machine (1); - support means (3; 103) for receiving said first conveyor means (2) and for supporting said group of products (100) and including first fastening means (4; 104) arranged to support an initial fin (51a ) of said part (51) of film when packing said group of products (100); - a packaging unit (10) for wrapping with a portion (51) of film (50) having a predetermined length said group of products (100), supported by said support means (3; 103), for the purpose of forming a package (200); - a unit (30) for supplying said film (50) for feeding said packaging unit (10) with said film part (51) having a predetermined length, separated from said film (50) unwound from a reel (55) ) respective; - containment means (6; 60) arranged to rest on at least side walls of said group of products (100) in order to support and guide said products (100) when the latter move along said direction (A) moving through said packaging unit (10) and / or supporting and containing said group of products (100) during packaging with said film part (51) (50); characterized in that said first fastening means include at least one support element (104) of said support means (103), said support element (104) comprising a support wall (141) forming a plane ( M) of support for said group of products (100) and means (40) of air suction, specifically, which exit at a base wall (148) of said support element (104) opposite to said wall (141) ) of support, and arranged to absorb and support by depression said initial flap (51a) of said part (51) of film during packaging, wherein said support element (104) of said support means (103) comprises a pair of first tapes (142), which are flexible, endless and arranged so that said part (51) of film is supported on respective sections (T) during the packing, said first tapes ( 142) for the purpose of moving in the sections (T) of operation or respective along said direction (A) of travel together with said package (200) leaving said packaging unit (10) to allow said support element (104) to separate from said package (200). 2. Packaging machine to pack groups of products (100) with an extendable plastic film (50) to form packages (200), comprising: - first conveyor means (2) for supporting and moving a group of products (100) along a direction (A) of movement inside the packaging machine (1); - support means (3; 103) for receiving said first conveyor means (2) and for supporting said group of products (100) and including first fastening means (4; 104) arranged to support an initial fin (51a ) of said part (51) of film when packing said group of products (100); - a packaging unit (10) for wrapping with a portion (51) of film (50) having a predetermined length said group of products (100), supported by said support means (3; 103), for the purpose of forming a package (200); - a unit (30) for supplying said film (50) for feeding said packaging unit (10) with said film part (51) having a predetermined length, separated from said film (50) unwound from a reel (55) ) respective; - containment means (6; 60) arranged to rest on at least side walls of said group of products (100) in order to support and guide said products (100) when the latter move along said direction (A) moving through said packaging unit (10) and / or supporting and containing said group of products (100) during packaging with said film part (51) (50); characterized in that said first fastening means comprise two support elements (4) of said support means (3), which are adjacent and opposite and provided with respective support walls (41) forming a plane (M) of support for said group of products (100), said support elements (4) being movable transversely with respect to said direction (A) of movement between a closing position (B1), where they are supported against each other in order to block said initial fin (51a), and an opening position (B2), where they are mutually separated in order to allow inserting or releasing said initial fin (51a), wherein each support element (4) comprises a first tape ( 42) respective that is flexible, endless and arranged so that said part (51) of film is supported on the same during a stretch (T) during packing, said first tape (42) being operated for that purpose moving in said operating section (T) along said direction (A) of movement together with said package (200) leaving said packing unit (10) to allow said support elements (4) to separate of said package (200). 3. Machine according to claim 1 or 2, wherein said packing unit (10) comprises an insertion arm (11) that is movable and arranged to hold said initial fin (51a) of said part (51) of film coming out of said supply unit (30) and to transfer it to said first fastening means (4; 104) for the purpose of being held and locked by the latter, in an initial stage of packing adjustment. 4. Machine according to any of the preceding claims, wherein said containment means (6; 60) comprise a pair of side panels (65; 261) suitable for resting on side walls of said products (100) inside said unit (10) of packaging, said side panels (65; 261) having a flat and elongated shape in order to facilitate the separation of said package (200) and the exit thereof from the packaging unit (10) at the end of the packaging. Machine according to claim 4, wherein said containment means (60) comprise a pair of support doors (262), each of which is rotatably fixed to the respective side panel (261) and being movable between a position of closure, where the support door is turned towards the opposite side panel (261) in order to block said products (100) that move along said direction (A) of movement, and an opening position, where the support door is at least almost aligned with the respective side panel (261) to allow the passage of products (100) that move along said direction (A) of travel and, therefore, leaving said packing unit (10). Machine according to claim 5, comprising additional pusher means (270) acting upstream with respect to said group of products (100), partially introduced into said packaging unit (10) by means of pusher means (26) of said first conveyor means (2), and arranged to push said product group (100) until the products are compacted against said support doors (262) that are arranged in a closed position. Machine according to claim 3, wherein said insertion arm (11) includes a first terminal part (11a) rotatably fixed to frame means of said machine (1) and a second terminal part (11b) provided with second means ( 21; 121; 221) suitable for holding said initial flap (51a) of said film part (51), said insertion arm (11) being rotatable between a holding position (G1), where it is adjacent to said supply unit (30) for the purpose of holding said initial fin (51a), and a transfer position (G2), wherein said insertion arm (11) is adjacent to said support means (3) for the purpose of transfer said initial fin (51a) to the first means (4; 104) for holding them.